<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
</head>
<body>

<%


    Integer number = (Integer) application.getAttribute("count");

    if (number == null || number == 0) {
        number = 1;
        application.setAttribute("count", number);
    } else {
        number++;
        application.setAttribute("count", number);
    }
%>

当前在线人数：<%=number%>
</body>
</html>